LVDT Transducers (Linear Variable Differential Transformer)

Image	Part Number	Description / PDF	Quantity	Rfq
	02560967-002 TE Connectivity Measurement Specialties	PTS 420-250 SERIES LVDT TRANSMIT	0
	02291279-000 TE Connectivity Measurement Specialties	LVDT AMPLIFIER	0
	02560551-000 TE Connectivity Measurement Specialties	GENERAL PURPOSE LVDT HR	0
	04290457-000 TE Connectivity Measurement Specialties	POSITION SENSOR	0
	02560446-000 TE Connectivity Measurement Specialties	GENERAL PURPOSE LVDT	0
	02291277-000 TE Connectivity Measurement Specialties	LVDT AMPLIFIER	0
	02291278-000 TE Connectivity Measurement Specialties	LVDT AMPLIFIER	0
	72350003-000 TE Connectivity Measurement Specialties	SENSOR	0
	04290577-000 TE Connectivity Measurement Specialties	POSITION SENSOR	0
	02291280-000 TE Connectivity Measurement Specialties	LVDT AMPLIFIER	0
	02560406-000 TE Connectivity Measurement Specialties	LVDT SENSOR 3/8" OD X .535" .010	0
	02350614-000 TE Connectivity Measurement Specialties	SPRING LOADED SENSOR GAUGE HEAD	0
	02560392-000 TE Connectivity Measurement Specialties	GENERAL PURPOSE LVDT HR	0
	02350712-000 TE Connectivity Measurement Specialties	LINEAR TRANSDUCER	0
	02520003-000 TE Connectivity Measurement Specialties	LINEAR TRANSDUCER	0
	02560996-000 TE Connectivity Measurement Specialties	SENSOR LVDT	0
	02560443-000 TE Connectivity Measurement Specialties	GENERAL PURPOSE LVDT	0
	72350001-000 TE Connectivity Measurement Specialties	SENSOR	0
	02560556-000 TE Connectivity Measurement Specialties	GENERAL PURPOSE LVDT HR	0
	02560445-000 TE Connectivity Measurement Specialties	HCD SERIES HERMETICALLY SEALED	0

LVDT Transducers (Linear Variable Differential Transformer)

1. Overview

Linear Variable Differential Transformers (LVDTs) are electromechanical sensors that convert linear displacement into electrical signals. As a type of inductive transducer, LVDTs operate on transformer principles to provide precise, contactless position measurements. Their inherent reliability, infinite resolution, and robustness in harsh environments make them critical in industries requiring high-precision motion control, such as aerospace, automotive testing, and industrial automation.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
AC-LVDT	Requires external signal conditioning; high accuracy and durability	Aerospace flight control systems
DC-LVDT	Integrated electronics for direct voltage output; easier to interface	Industrial automation sensors
PCB-Mounted LVDT	Compact design for printed circuit board integration	Medical diagnostic equipment
High-Temperature LVDT	Operates up to 400 C with specialized insulation materials	Power plant valve position monitoring
Submersible LVDT	Hermetically sealed for underwater/wet environment use	Hydraulic cylinder position feedback

3. Structure and Components

Typical LVDT construction includes:

Core: Ferromagnetic movable element coupled to the target
Primary Coil: Center coil driven by AC excitation
Secondary Coils: Symmetrical differential windings (S1 and S2)
Bobbin: Cylindrical polymer or ceramic structure housing coils
Shield: Electromagnetic interference protection (often stainless steel)

Operation principle: The core's position modulates magnetic coupling between primary and secondary coils, generating a differential voltage proportional to displacement.

4. Key Technical Specifications

Parameter	Significance
Measurement Range	Defines operational displacement limits (typically 0.1mm to 250mm)
Linearity Error	Maximum deviation from ideal transfer function (0.05-0.25% FS)
Resolution	Theoretical minimum detectable displacement (down to 0.1 m)
Frequency Response	Dynamic measurement capability (up to 20kHz for AC-LVDTs)
Temperature Range	Operating limits (-55 C to +150 C standard)
IP Rating	Environmental protection level (IP60 to IP68 available)

5. Application Fields

Industrial: Servo valve position control, CNC machine tool monitoring
Automotive: Suspension travel analysis, brake wear measurement
Aerospace: Flight surface position sensing, landing gear deployment
Medical: MRI table positioning, robotic surgical device feedback
Energy: Nuclear reactor rod position monitoring, wind turbine pitch control

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
TE Connectivity	DC-LVDT 5LV Series	0.25% linearity, 0-20V DC output, IP68
Macro Sensors	AC16 Series	0.05% non-linearity, 3kHz bandwidth
Honeywell	976SC Series	Submersible design, 0.1 m resolution
DLCI Electronics	Model 3800	High-temperature capability (up to 400 C)

7. Selection Guidelines

Key considerations:

Required measurement range vs. linearity tradeoffs
Environmental conditions (temperature, vibration, contamination)
Electrical interface compatibility (AC/DC, analog/digital)
Physical installation constraints (space, mounting options)
Cost vs. performance optimization

8. Industry Trends

Emerging developments include:

Nanometer-resolution MEMS-based LVDTs for semiconductor manufacturing
Wireless-enabled smart transducers with integrated IoT connectivity
Additive manufacturing of custom coil geometries
Advanced thermal compensation algorithms via embedded microprocessors
Increased adoption in autonomous vehicle sensor fusion systems